Do you mean that a) you want to select only those rows in which item_code is a number - e.g., you have 1234 and abc24 in two rows, and you want to get only one row out of those two - the one that has 1234

orb) your item_code is a combination of digits and other characters, and you want to pick out the numbers out of those? e.g., you have 1234 and abc24 in two rows and you want to get two rows with item_codes as 1234 and 24?